Below is a link to another board The Stovebolt page for old chevy/gmc trucks.
The thread linked to includes very specific information on what hammers and dollies to buy, tool choices, and a very well written tutorial on body work (better than any book I've read).
Pay close attention to MARTINSRs posts - he has been doing this for a very long time.
http://www.stovebolt.com/bboard/cgi-bin//ultimatebb.cgi?ubb=get_topic;f=4;t=001805
- Ryan